Automatic switch



Feb. 12, 1929.

P. B. PARKS ET AL AUTOMATIC SWITCH Original F Patented Feb. 12, 1929.

UNITED STATES PATENT OFFICE.

PAUL B. PARKS, 0F OAK PARK, AND DONALD V7. MILLER, OF ELIVHURST, ILLINOS,

ASSIGNORS T0 VAPOR CAR HEATNG CORPORATION 0F NEW YORK.

COIPANY, INC., OF CHICAGO, LLINOIS, A

AUTOMATIC SWITCH.

Original application led February 2, 1927, Serial No. 165,392, and in Sweden August 14, 1925. Divided and this application filed October 5, 1927.

rthis intention relates to a new and improved automatic selector switch, which is ot general application but is particularly adapted for use in connection with a car heating system such as is disclosed in our copending application, Serial No. 165,392, tiled February 2, 1927, in which this selector switch was first disclosed, and of which parent application this present application is a division.

This in'iproved switch comprises av Bourdon tube which is closed at one end and is .in open communication at the other end with a pipe line on the car which contains air or other iiuid under pressure when the car is connected in service in a t-r in. The tree closed end of the Bourdon tube is connected through quick-motion mechanism with a movable switch-plate or bridge-plate adapted to be moved into or out of engagement with a plurality oi' liXed spring contacts so as to term an electrical connection between these several contacts. Mechanism is also provided .tor manually moving one of the spring contacts out oi engagement with the bridge-plate, even though these contacts have been brought into engagement automatically by the withdrawal ot lluid pressure from the Bourdon tribe. Automatic means is provided whereby this manually operated mechanism will be automatically moved back to disengaged position when fluid pressure is returned to the tube.

yihe principal object ot this invention is to provide an automatic selector switch constructed and *functioning in the manner briellly indicated hereinabove, and as described more in detail hereinafter.

Another object is to provide means in connection with said selector switch whereby a portion ot the circuits automatically closed by this switch may be broken manually in emergency conditions, this emergency mechanism being' automatically thrown outoit operation so that the parts will be returned to their normal positions.

Other objects and advantages ot' this invention will be apparent from the following detailed description ot one approved form ot the mechanism.

In the accompanying drawings:

Fig'. l an elevation ot the automatic se- Serial No. 224,184.

lector switch, with the cover plate of the enclosing casing remoif'od.

Fig' is a vertical section, taken substantiaily on the line ot Fig'. l.

l is an elevation ot' a portion oi' the switch operati g mechanism, the manually operable releasing mechanism being removed io disclose the parts located thereinunder, and other parts being rroken away to tacilitate the disclosure.

ln our parent application, Serial No. 165 392, hereinabove referred to, we have disclosed an eieci'irical control system 'tor regulating the tcn'iperatures in a plurality of separate compartments oil a railway car. This r dating' system comprises a number ot control circuits, two of which are antoinatically opened or closed by the automatic selector switch hereinafter described.

rlfhe automatic selecto".` switch K, with which the subjectanatter oit the present application is particularly concerned, comprises a casing' 67 in which is mounted a Bourdon tube 68, preterably olf the shape and cross section indicated in Figs. l and 2. -The tree end. G9 ot this tube is closed, and the other end mounted on and is in open communication with the pipe leading to the main air line on thc car. Three similar spring contacts 7l, 7 2 and 73 are mounted in parallel relation on an insulating block 74 within casing 6.7. The contacts 7l and 72 are in one ot the control circuits of the heating system, and contacts 72 and 73 are in a second circuit, all as disclosed in detail in said parent application. ri swinging contact plate 75 mounted on insuhiting` block 76 is adapted to bridge these three contacts 7l, 72 and 7 S when in the position shown in Figs. l and 2. Vhen swung` up to the position indicated in dotted lines in Fig. 3, the plate 7 will be out ot' contact with the several spring contacts 71, 72 and 73 so that there w'll be no electrical connection between any two of these contacts. The insulating block 7 .t which carries movable contact 75 is mounted on a plate 77 which is pivoted on the fixed post 7 S. Plate 77 has at one side a triangular projection 79 adapted to be engaged by a roller 8O mounted in the 'tree end of a link 8l, pivoted at 82 on a bellcrank 83, which is mounted on a. fixed pivot S4. Link 81 is con-- stantly urged toward the right in Figs. 1 and 3 by means oit the contraction spring 85, one end ot which is secured to the link 812 and the other to a fixed portion of the supporting framework at 85. which link is adjustable at 87, is connected at one end 88 to the tree end 69 of the Bourdon tube (i8, and is adjust-ably connected at its other end 89 within a slot 90 in one arm of bellcrank 83. When the car is out oit' service and the air pressure in pipe and Bonrdon tube 68 is dissipated, thisftube Will contract so that the tree end G9 will move inwardly and downwardly and the partsot the s fitch mechanism will assume the positions shown ini.I l and 3. The roller will be in engagement with the upper inclined surface otprojection 79 and will hold the bridge plate 7 5in-engagement with the spring contacts 7l, 7-2 and 73. When super-atmospheric air pressure is returned to the pipe 7 @,t'he tube=68 will tend to straighten and will pull up on the link 86, swinging bellerank 83 in a counter clockwise direction and drawingdown tfhelink 8l, the roller 8O inoving;- downwardly and to the lett along` the inclined surface or projection'7 9 until it passes the pointed end of this projection. The spring 85 will then draw the roller to the right along the-downwardlyinclined surface of projection 79, thusV quickly rotating the plate 77 in a clockwise direction and quickly swinging' the bridge plate 7 5 out of Contact with the spring' contact-s 7l, 72 and 73. TWhen the air pressurei'sreleased from pipe'70 and Bourdon. tube 68, a reversal oi these movement-s will 'take place and the contact plate 75 will be quickly snapped back into the position shown in Figs-1 and 2 so that the contacts 7l, 72 and 73'a're againV placed in electrical connection with one another by means of bridge plate 75. A projecting finger onthe lett-hand arm ot bel-lcrank 83 is adapted to engage the yfixed pin l151 to limit movement ot the partsto the switch-closing position' shown in Figs. l and 3. The lower fined plate 152 and upper lined plate 153 serve as anchoring means for the several pivot pins and' abutment pins. Y

Undcrcertain' conditions it is desirable to break the electrical connectiony between spring,y contact 73 and bridge plate 75 without disturbing the connection between contacts 7l and 72 andthe plate 75. Accordingly,.means a'refiarovided tor independently pushing" back the spring; contact 73 out oft contact with plate 75 wnen the parts are in the positions shown' in Figs. l and 3. n. plate 91 pivoted on the' central post 154- carrics ahlock oiinsulating material 9.2., which, when the plate is swung' in a clockwise direction from lthe position shown in Fig. 1,'engages the spring' Contact 73 and pushes it back to the position shown in dotted lines in'Fi'g'. 2 and out oi" contact with'v the bridge plate 75.

A composite link 86,.

'99, having'. one end lined and the other end engaging the arm 93, tends to swing the plate 91 into the'inoperative'position'show-n iii-fullv lines in Fio'.- 13.- l'lowever when the s nina' rchimp 97 is in engagement with the end ot post the iiisulating'v block 92 willA be held infits'ope 'ative engagement so asto push back the spring" contact 73, the coil spring' 9.9

being at such time under tension. Nhen the bellcrank 83 is swung down by the expansion ot the Bourdon tube @Sso as to swing up the Contact plate 75 to its ciinuit-breaking' position7 as shown` in dotted lines in Fig. 3, the post 98-will be moved down out ot engage' n'ient with the spring; clama 97 thus leavina l .n l, i

the spring 99 .tree to swing' kthe plate 91 back to its inoperative positionneindicat'ed inFig'. l. An operating, knob or handle 200 is secured centrally to theplate 91 and extends through the cover l Viate 156 of casing; 67 so that it n'iay be manually grasped to swing' hc releasing' plate 91 to either of vits two positions. constitutes an emergency switch whic i isopcrated whenl the car is out ot service, it it is desired to heat the car to one ot the higher temperatures. lt will be apparent that even though' this emergency switch has been operated, it'will be automatically returned to its inoperative posit-ion by the spring' 99 w ien the is again'put in serv-ice and fluid pressure is returned to the Bourdon tube 68.

le claim:

l. A; pressure-operated selector switch comprising;- Aaf-plnrality ot spring' contacts, a mm'- able tch-plate. fluid-pressure operated means torinoving; the switch-plate into or out i, gement with the spring' contactaan'd means for independently moving' one of the spring-contacts out of engagement 'with the switch-plate; Y

2, A; pressure-'operated selector switch comprisma' a plurality of spring contacts, a movable switch-plataV fluid-pressure operated means torinoving' the switch plate into or ont o'l engagement with the spring' contacts, releasing means movable into engagement with one ot the spring,r contacts to hold it out of engagement with the switch-plate, a spring for automatically returning' the releasing' means to its inoperative' position, and a latch for holding the releasing' means' in engagement with the sprii'igF contact, the latch being released when the fluid-pressure operated means moves the switch-plate out of engagement with the spring contacts.-

3. A pressure-operated-selector-switch-com- The n'iechanism just described 'ing arm 96, extending from arm 93, has

prising a plurality of spring contacts, a movable switch-plate, Huid-pressure operated means for moving the switch plate into or out of engagement with the spring contacts, releasing means movable into engagement with one oi? the spring cont-acts to hold it out of engagement with the switch-plate, a spring for. automatically rt-turning the releasing means to its inoperative position, a latch on the releasing means, and an abutment on a portion oit the fluid-pressure operated means engaged by the latch to hold the releasing means in operative position only while the switch-plate is in engagement with the spring-contacts.

4. A pressure-operated selector switch comprising a Bourdon tube, a plurality of spring contacts, a movable switch plate adapted in one position to engage and electrically connect the spring contacts, connections between the Yfree end ot the tube and the movable switch plate adapted to move the plate into or out ol contact making position, and means 'tor nmving one ot' the spring contacts out ot engagement with the switch plate.

5. A pressure-operated selector switch comprising a Bourdon tube, a plurality of spring contacts, a movable switch plate adapted in one position to engage and electrically connect the spring contacts, connections between the free end oi the tube and the movable switch plate adapted to move the plate into or out of contact making position, means movn able into engagement with one of the spring contacts for springing it back out of engagement with the switch plate, and means for auton'iatically returning the last named means to inoperative position.

6. A l'n'essure-operated selector switch comprising a Bourdon tube, a plurality of spring contacts, a movable switch plate adapted in one position to engage and electrically connect the spring contacts, connections between the free end of the tube and the movable switch plate adapted to move the plate into or out ot contact making position, a block movable into engagement with one ot' the spring contacts tor moving it back out of engagement with the switch plate, a spring for returning the block to inoperative position, and a latch for holding the block in operative position against the action of the spring, the latch being released by the movement of the switch plate to contact-breaking position.

7. A pressure operated selector switch comprising a Bourdon tube, a plurality of spring contacts, a movable switch plate adapted in one position to engage and electrically connect the spring contacts, quick-motion connections between the tree end of the tube and the switch-plate adapted to move the plate into or out olf contact-making position, said connections comprising a pivoted plate, a block movable into engagement with one ot the spring contacts for moving it back out of engagement with the switch plate, a spring for returning the block to inoperative position, a spring-latch connected with the block, and an aiiuitment on the pivoted plate enga ged by the latch to hold the block against the action of the spring, the abutment being moved out of engagement with the latch when the switch-plate is moved to contact-breaking position.

8. A pressure-operated selector switch comprising a. Bourdon tube, a plurality of spring contacts, a pivoted switch-plate adapted to be swung into or out of engagement with the spring contacts, there being a cam projection on the switch-plate, a bell-crank lever, a link connecting one arm of the bellcrank with the tree end of the Bourdon tube, a link pivoted at one end to the other arm of the bellcrank, a roller pivoted in the free end of the link and engaging the cam, and a spring mounted to urge the roller toward the cam.

9. A pressure operated selector switch comprising a Bourdon tube, a plurality of spring contacts, a pivoted switch-plate adapted to be swung into or out of engagementwith the spring contacts, there being a cam projection on the switch-plate, a bellcrank lever, a link connecting one arm of the bellcranl: with the free end of the Bourdon tube, a link pivoted at one end to the other arm oit the bellcranl, a roller pivoted in the free end of the link and engaging the cam, a spring mounted to urge the roller toward the cam, a pivoted member movable into engagement with one of the spring contacts to move it out of engagement with the switch-plate, a spring tending to return the pivoted member to inoperative position, a spring-latch on the pivoted member, and an abutment on the bellcrank engaged by the latch to hold the member in operative position.

PAUL B. PARKS. DONALD W. MILLER. 

